EP0394072A2 - Rotary reflecting devices for use in optical scanning apparatus - Google Patents

Rotary reflecting devices for use in optical scanning apparatus Download PDF

Info

Publication number
EP0394072A2
EP0394072A2 EP90304305A EP90304305A EP0394072A2 EP 0394072 A2 EP0394072 A2 EP 0394072A2 EP 90304305 A EP90304305 A EP 90304305A EP 90304305 A EP90304305 A EP 90304305A EP 0394072 A2 EP0394072 A2 EP 0394072A2
Authority
EP
European Patent Office
Prior art keywords
reflecting
axis
rotation
polygon mirror
faces
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP90304305A
Other languages
German (de)
French (fr)
Other versions
EP0394072A3 (en
EP0394072B1 (en
Inventor
Hiroaki Katoh
Yoshitaka Murakawa
Toshimasa Miyazaki
Nobuyuki Kitamura
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Publication of EP0394072A2 publication Critical patent/EP0394072A2/en
Publication of EP0394072A3 publication Critical patent/EP0394072A3/en
Application granted granted Critical
Publication of EP0394072B1 publication Critical patent/EP0394072B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/08—Mirrors
    • G02B5/09—Multifaceted or polygonal mirrors, e.g. polygonal scanning mirrors; Fresnel mirrors

Definitions

  • This invention relates to rotary reflecting devices for use in optical scanning apparatus, for example apparatus for scanning coded bars by means of a laser beam to read a bar code of the coded bars.
  • POS (point of sales) systems have been introduced in many department stores and supermarkets in order to improve the efficiency in management of commodities and checking out operations.
  • a bar code reader including an optical scanner is used, which scans coded bars attached to a commodity by means of a laser beam, detects diffused signal light from the coded bars by means of a photodetector and converts it into a signal having a form of information suitable for subsequent calculation processing.
  • a bar code reader commonly comprises a laser beam generating source, a laser beam shaping optical system, a scanning optical system, a signal light detecting optical system, a wave form shaping circuit and a bar code demodulating circuit.
  • a laser beam emitted from a He-laser is shaped into a laser beam of a suitable size by the beam shaping optical system, and a scanning pattern for the universal reading is formed with the thus shaped laser beam by the scanning optical system and the laser beam is caused to irradiate the coded bars with the scanning pattern.
  • Diffused light reflected from the coded bars is condensed by the signal light detecting optical system and the signal light is converted into an electric signal by the photodetector.
  • the electric signal is shaped by the signal waveform shaping circuit and then converted into a numerical value by the bar code demodulating circuit, and the numerical value thus obtained is transmitted to a POS terminal.
  • optical scanners for use with such bar code readers have been proposed and put into practical use, they can be roughly divided into two types, one of which employs a rotary reflecting device, such as a polygon(al) mirror, and the other of which employs a hologram disk.
  • Conventional optical scanners of either of the two types are commonly disadvantageous in that, since a scanning pattern generating mirror device including a plurality of reflecting mirrors must be provided in order to obtain a scanning pattern which is composed of a plurality of scanning lines of various directions, the number of components is increased, and the cost is high, and in addition miniaturization of the device cannot be achieved. Further, in order to obtain a long or large beam pattern, the reflecting mirrors must necessarily be large in size, which also causes a rise in cost and an obstacle to miniaturization of the device.
  • optical scanning apparatus which can be reduced in size and in production cost as compared with prior art optical scanners.
  • An embodiment of the present invention can provide a rotary reflecting device which is suitable for generating a scanning pattern formed from a plurality of scanning lines of different directions.
  • an optical scanner for scanning coded bars by means of a laser beam to read a bar code of the coded bars, which comprises a light source for generating a laser beam, a rotary polygon mirror having a plurality of reflecting portions provided thereon around an axis of rotation thereof for reflecting the laser beam from the light source toward the coded bars, each of the reflecting portions of the rotary polygon mirror including a plurality of flattened reflecting faces having different inclination angles from each other with respect to the axis of rotation such that an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of the reflecting portions with respect to the axis of rotation is different from an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of adjacent ones of the reflecting portions on the opposite sides of the reflecting portion with respect to the axis of rotation, and a photodetector for detecting diffused signal light diffused by the coded bars.
  • an included angle between adjacent ones of the flattened reflecting faces of each of the reflecting portions of the rotary polygon mirror is different from an included angle between adjacent ones of the flattened reflecting faces of adjacent ones of the reflecting portions on the opposite sides of the reflecting portion.
  • a rotary polygonal mirror adapted to produce a scanning pattern constituted from a plurality of scanning lines of different directions, the rotary polygon mirror having a plurality of reflecting portions provided around an axis of rotation thereof, each of the reflecting portions having a plurality of flattened reflecting faces having different inclination angles from each other with respect to the axis of rotation such that an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of the reflecting portions with respect to the axis of rotation is different from an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of adjacent ones of the reflecting portions on the opposite sides of the reflecting portion with respect to the axis of rotation.
  • a reading window 12 is provided at the top of a casing 10.
  • a light source 14 for generating a laser beam such as a He-Ne laser or the like, is provided in the casing 10, and a laser beam LB emitted from the light source 14 is reflected by a mirror 16 and onto a rotary reflecting device, comprising a polygon mirror 18 which embodies the second aspect of the present invention.
  • the rotary polygon mirror 18 has a plurality of reflecting portions (reflectors) 20 on an outer periphery thereof and is rotated around an axis of rotation thereof by a motor 22.
  • the laser beam LB reflected by a reflecting portion 20 of the rotary polygon mirror 18 scans coded bars 26 attached to a commodity 24. Since the reflecting portions 20 of the rotary polygon mirror 18 have different reflecting directions for a beam as hereinafter described, the rotary polygon mirror 18 produces a scanning pattern which is composed of a plurality of scanning lines of different directions so that the laser beam may scan the entire coded bars 26 attached to the commodity 24 irrespective of the orientation of the coded bars 26. Diffused signal light diffused by the coded bars 26 is once reflected by the reflecting portion 20 of the polygon mirror 18 and condensed to or focused upon a photodetector 30 by a condenser or focussing lens 28 as indicated by broken lines in FIG. 1.
  • the rotary polygon mirror 18 has a plurality (6 in the present embodiment) of reflecting portions 20 disposed around the rotational axis thereof, and each of the reflecting portions 20 includes a pair of reflecting faces 20a and 20b.
  • each of the reflecting portions 20 includes a pair of reflecting faces 20a and 20b.
  • ⁇ 1 an angle defined by a line 21 of intersection between the reflecting faces 20a and 20b of each of the reflecting portions 20 and the axis 18a of rotation of the rotary polygon mirror 18
  • the rotary polygon mirror 18 is formed such that the value of the angle ⁇ 1 of each of the reflecting portions 20 thereof may be different from those angles ⁇ 1 of adjacent reflecting portions 20 on the opposite sides of the reflecting portion 20.
  • the rotary polygon mirror 18 is formed also such that the value of the angle ⁇ 2 of each reflecting portion 20 thereof may be different from the included angles ⁇ 2 of adjacent reflecting portions 20.
  • the rotary polygon mirror 18 is formed such that it has six reflecting faces 20 and the values of ⁇ 1 and ⁇ 2 of each of the reflecting portions 20 are different from the values of ⁇ 1 and ⁇ 2 of adjacent reflecting portions 20 on the opposite sides of the reflecting portion 20, respectively.
  • Each pair of those of the reflecting portions 20 which are positioned on the opposite sides with respect to the axis 18a of rotation are equal in inclination angle ⁇ 1 and included angle ⁇ 2 to each other.
  • a laser beam LB emitted from the light source 14 is reflected by the mirror 16 onto the rotary polygon mirror 18.
  • the laser beam LB reflected by the reflecting face 20a of a reflecting portion 20 of the rotary polygon mirror 18, which is rotating at a high speed, is reflected again by the other, opposing reflecting face 20b and scans coded bars 26 of a commodity 24 through the reading window 12.
  • the angle ⁇ 1 is otherwise equal among all of the reflecting faces 20 of the rotary polygon mirror 18 while only the angle ⁇ 2 varies between each adjacent ones of the reflecting faces 20, then a pattern with which the laser beam LB is to scan the coded bars 26 is constituted from a plurality of such parallel scanning lines of the same direction as seen in FIG. 5.
  • Diffused signal light from the coded bars 26 advances reversely along the passage of the scanning beam and is thus reflected by the rotary polygon mirror 18 and then focused upon the photodetector 30 by the condenser lens 28.
  • the photodetector 30 converts the received diffused signal light into an electric signal, which is then converted into a digital signal by an analog to digital converter not shown and decoded by a bar code demodulating circuit.
  • a scanning pattern which is composed of a plurality of scanning lines of various directions can be produced using only the rotary polygon for 18. Accordingly, a hologram disk or a set of reflecting mirrors such as are used in a conventional optical scanner can be eliminated, which enables miniaturization and reduction in cost of the arrangement. Further, if the rotary polygon mirror 18 is formed by molding a body from a resin material and applying an aluminum film on the resin body by vapor deposition to form reflecting faces, it can be produced at even lower cost. Further, since a laser beam is reflected a comparatively small number of times, the amount of light required can be minimized, and hence the output power of the light source 14 can be reduced.
  • FIG. 8 Another optical scanner embodying the first aspect of the present invention will now be described with reference to FIG. 8. It is to be noted that, since the optical scanner of the present embodiment has somewhat similar construction to that of the optical scanner of the preceding embodiment, substantially like components are denoted by like reference numerals and overlapping description thereof is omitted herein to avoid redundancy.
  • the optical scanner of the present embodiment includes a mirror 36 for changing the advancing direction of diffused signal light condensed by a condenser lens 28 and adopts a hollow rotary polygon mirror 32 comprising a substantially hexagonal tube which is open at the top thereof.
  • a plurality (six in the present embodiment) of reflecting portions 34 are provided on an inner periphery of the rotary polygon mirror 32 and are each constituted from a pair of opposing reflecting faces 34a and 34b.
  • the reflecting faces 34a and 34b of the reflecting portions 34 are disposed such that such a scanning pattern which is composed of a plurality of scanning lines of various directions as seen in FIG. 7 may be obtained similarly as in the embodiment described above.
  • the optical scanner of the present embodiment has such construction as described just above, a scanning pattern constituted from a plurality of scanning lines of various directions can be obtained using only the rotary polygon mirror 32 similarly as in the optical scanner of the preceding enbodiment.
  • optical scanner of the present embodiment further has such advantages as those of the optical scanner of the embodiment described hereinabove.
  • each of the reflecting portions of the rotary polygon mirror has a pair of reflecting faces having different inclination angles with respect to the axis of rotation of the rotary polygon mirror
  • the number of such reflecting faces of each reflection portion is not limited to two.
  • each reflecting portion 38 may include three reflecting faces 38a, 38b and 38c having different inclination angles with respect to the axis of rotation of the rotary polygon mirror.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Mechanical Optical Scanning Systems (AREA)
  • Facsimile Scanning Arrangements (AREA)

Abstract

A rotary reflecting device (18; 32), for use in optical scanning apparatus, of the type being rotatable about an axis of rotation therethrough and having a plurality of reflectors (20; 38) positioned at respective different angular locations around that axis, is characterised in that each of the said reflectors (20; 38) has two mutually-adjacent substantially planar reflecting faces (20a, 20b; 38a, 38b) which meet in a line (21) of intersection that is inclined with respect to the said axis of rotation, and in that the respective said lines (21) of intersection of adjacent reflectors (20; 38) of the device are inclined respectively at different angles (ϑ₁) with respect to the said axis of rotation.
The use of such a rotary reflecting device in optical scanning apparatus, for reading bar codes for example, can enable a satisfactory scanning pattern to be produced without the need for additional, and/or comparatively large, components such as are required in prior art optical scanning apparatus, thereby permitting a reduction in the overall size and cost of the apparatus.

Description

  • This invention relates to rotary reflecting devices for use in optical scanning apparatus, for example apparatus for scanning coded bars by means of a laser beam to read a bar code of the coded bars.
  • POS (point of sales) systems have been introduced in many department stores and supermarkets in order to improve the efficiency in management of commodities and checking out operations. In such systems, a bar code reader, including an optical scanner is used, which scans coded bars attached to a commodity by means of a laser beam, detects diffused signal light from the coded bars by means of a photodetector and converts it into a signal having a form of information suitable for subsequent calculation processing. Such a bar code reader commonly comprises a laser beam generating source, a laser beam shaping optical system, a scanning optical system, a signal light detecting optical system, a wave form shaping circuit and a bar code demodulating circuit. Typically, a laser beam emitted from a He-laser is shaped into a laser beam of a suitable size by the beam shaping optical system, and a scanning pattern for the universal reading is formed with the thus shaped laser beam by the scanning optical system and the laser beam is caused to irradiate the coded bars with the scanning pattern. Diffused light reflected from the coded bars is condensed by the signal light detecting optical system and the signal light is converted into an electric signal by the photodetector. The electric signal is shaped by the signal waveform shaping circuit and then converted into a numerical value by the bar code demodulating circuit, and the numerical value thus obtained is transmitted to a POS terminal.
  • While various types of optical scanners for use with such bar code readers have been proposed and put into practical use, they can be roughly divided into two types, one of which employs a rotary reflecting device, such as a polygon(al) mirror, and the other of which employs a hologram disk. Conventional optical scanners of either of the two types are commonly disadvantageous in that, since a scanning pattern generating mirror device including a plurality of reflecting mirrors must be provided in order to obtain a scanning pattern which is composed of a plurality of scanning lines of various directions, the number of components is increased, and the cost is high, and in addition miniaturization of the device cannot be achieved. Further, in order to obtain a long or large beam pattern, the reflecting mirrors must necessarily be large in size, which also causes a rise in cost and an obstacle to miniaturization of the device.
  • Accordingly, it is desirable to provide optical scanning apparatus which can be reduced in size and in production cost as compared with prior art optical scanners.
  • An embodiment of the present invention can provide a rotary reflecting device which is suitable for generating a scanning pattern formed from a plurality of scanning lines of different directions.
  • In accordance with a first aspect of the present invention, there is provided an optical scanner for scanning coded bars by means of a laser beam to read a bar code of the coded bars, which comprises a light source for generating a laser beam, a rotary polygon mirror having a plurality of reflecting portions provided thereon around an axis of rotation thereof for reflecting the laser beam from the light source toward the coded bars, each of the reflecting portions of the rotary polygon mirror including a plurality of flattened reflecting faces having different inclination angles from each other with respect to the axis of rotation such that an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of the reflecting portions with respect to the axis of rotation is different from an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of adjacent ones of the reflecting portions on the opposite sides of the reflecting portion with respect to the axis of rotation, and a photodetector for detecting diffused signal light diffused by the coded bars.
  • Preferably, an included angle between adjacent ones of the flattened reflecting faces of each of the reflecting portions of the rotary polygon mirror is different from an included angle between adjacent ones of the flattened reflecting faces of adjacent ones of the reflecting portions on the opposite sides of the reflecting portion.
  • In accordance with a second aspect of the present invention, there is provided a rotary polygonal mirror adapted to produce a scanning pattern constituted from a plurality of scanning lines of different directions, the rotary polygon mirror having a plurality of reflecting portions provided around an axis of rotation thereof, each of the reflecting portions having a plurality of flattened reflecting faces having different inclination angles from each other with respect to the axis of rotation such that an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of the reflecting portions with respect to the axis of rotation is different from an inclination angle of a line of intersection between adjacent ones of the flattened reflecting faces of each of adjacent ones of the reflecting portions on the opposite sides of the reflecting portion with respect to the axis of rotation.
  • Reference will now be made, by way of example, to the accompanying drawings, in which:-
    • FIG. 1 shows a schematic view of an optical scanner embodying the first aspect of the present invention;
    • FIG. 2 shows a perspective view of a rotary polygonal mirror embodying the second aspect of the present invention;
    • FIG. 3 shows a front elevational view of a portion of the rotary polygonal mirror shown in FIG. 2;
    • FIG. 4 shows a side elevational view of the portion shown in FIG. 3;
    • FIG. 5 is a diagrammatic representation of a scanning pattern;
    • FIG. 6 is a diagrammatic representation of another scanning pattern;
    • FIG. 7 is a diagrammatic representation of a further scanning pattern;
    • FIG. 8 shows a schematic view of another optical scanner embodying the first aspect of the present invention; and
    • FIG. 9 shows a schematic view of a portion of another rotary polygonal mirror embodying the second aspect of the present invention together with part of an optical scanner.
  • Optical scanning apparatus embodying the first aspect of the present invention will now be described with reference to FIGS. 1 to 7. Referring first to FIG. 1, a reading window 12 is provided at the top of a casing 10. A light source 14 for generating a laser beam, such as a He-Ne laser or the like, is provided in the casing 10, and a laser beam LB emitted from the light source 14 is reflected by a mirror 16 and onto a rotary reflecting device, comprising a polygon mirror 18 which embodies the second aspect of the present invention. The rotary polygon mirror 18 has a plurality of reflecting portions (reflectors) 20 on an outer periphery thereof and is rotated around an axis of rotation thereof by a motor 22. The laser beam LB reflected by a reflecting portion 20 of the rotary polygon mirror 18 scans coded bars 26 attached to a commodity 24. Since the reflecting portions 20 of the rotary polygon mirror 18 have different reflecting directions for a beam as hereinafter described, the rotary polygon mirror 18 produces a scanning pattern which is composed of a plurality of scanning lines of different directions so that the laser beam may scan the entire coded bars 26 attached to the commodity 24 irrespective of the orientation of the coded bars 26. Diffused signal light diffused by the coded bars 26 is once reflected by the reflecting portion 20 of the polygon mirror 18 and condensed to or focused upon a photodetector 30 by a condenser or focussing lens 28 as indicated by broken lines in FIG. 1.
  • Construction of the rotary polygon mirror 18 will be described with reference to FIGS. 2 to 4. The rotary polygon mirror 18 has a plurality (6 in the present embodiment) of reflecting portions 20 disposed around the rotational axis thereof, and each of the reflecting portions 20 includes a pair of reflecting faces 20a and 20b. Referring particularly to FIG. 3, where an angle defined by a line 21 of intersection between the reflecting faces 20a and 20b of each of the reflecting portions 20 and the axis 18a of rotation of the rotary polygon mirror 18 is represented by ϑ₁ , the rotary polygon mirror 18 is formed such that the value of the angle ϑ₁ of each of the reflecting portions 20 thereof may be different from those angles ϑ₁ of adjacent reflecting portions 20 on the opposite sides of the reflecting portion 20. Meanwhile, referring to FIG. 4, where an included angle between the reflecting faces 20a and 20b of each of the reflecting portions 20 of the rotary polygon mirror 18 is represented by ϑ₂, the rotary polygon mirror 18 is formed also such that the value of the angle ϑ₂ of each reflecting portion 20 thereof may be different from the included angles ϑ₂ of adjacent reflecting portions 20.
  • In particular, in the present embodiment shown in the drawings, the rotary polygon mirror 18 is formed such that it has six reflecting faces 20 and the values of ϑ₁ and ϑ₂ of each of the reflecting portions 20 are different from the values of ϑ₁ and ϑ₂ of adjacent reflecting portions 20 on the opposite sides of the reflecting portion 20, respectively. Each pair of those of the reflecting portions 20 which are positioned on the opposite sides with respect to the axis 18a of rotation are equal in inclination angle ϑ₁ and included angle ϑ₂ to each other.
  • In operation, a laser beam LB emitted from the light source 14 is reflected by the mirror 16 onto the rotary polygon mirror 18. The laser beam LB reflected by the reflecting face 20a of a reflecting portion 20 of the rotary polygon mirror 18, which is rotating at a high speed, is reflected again by the other, opposing reflecting face 20b and scans coded bars 26 of a commodity 24 through the reading window 12. Here, if the angle ϑ₁ is otherwise equal among all of the reflecting faces 20 of the rotary polygon mirror 18 while only the angle ϑ₂ varies between each adjacent ones of the reflecting faces 20, then a pattern with which the laser beam LB is to scan the coded bars 26 is constituted from a plurality of such parallel scanning lines of the same direction as seen in FIG. 5. On the other hand, if the angle ϑ₂ is equal among all of the reflecting faces of the rotary polygon mirror 18 while only the angle ϑ₁ varies between each adjacent ones of the reflecting faces 20, then a pattern with which the laser beam LB is to scan the coded bars 26 is constituted from such a plurality of scanning lines which intersect each other at a particular point as seen in FIG. 6. Accordingly, where both of the angles ϑ₁ and ϑ₂ vary between each adjacent ones of the reflecting portions 20 of the rotary polygon mirror 18 as in the embodiment described above, such a scanning pattern is produced which is constituted from a plurality of scanning lines of various directions as seen in FIG. 7. If the coded bars 26 on the commodity 24 are scanned with such a scanning pattern as described just above, the entire coded bars 26 can be scanned by at least one of such scanning lines irrespective of an orientation of the coded bars 26.
  • Diffused signal light from the coded bars 26 advances reversely along the passage of the scanning beam and is thus reflected by the rotary polygon mirror 18 and then focused upon the photodetector 30 by the condenser lens 28. The photodetector 30 converts the received diffused signal light into an electric signal, which is then converted into a digital signal by an analog to digital converter not shown and decoded by a bar code demodulating circuit.
  • With the optical scanner of the construction described above, a scanning pattern which is composed of a plurality of scanning lines of various directions can be produced using only the rotary polygon for 18. Accordingly, a hologram disk or a set of reflecting mirrors such as are used in a conventional optical scanner can be eliminated, which enables miniaturization and reduction in cost of the arrangement. Further, if the rotary polygon mirror 18 is formed by molding a body from a resin material and applying an aluminum film on the resin body by vapor deposition to form reflecting faces, it can be produced at even lower cost. Further, since a laser beam is reflected a comparatively small number of times, the amount of light required can be minimized, and hence the output power of the light source 14 can be reduced.
  • Another optical scanner embodying the first aspect of the present invention will now be described with reference to FIG. 8. It is to be noted that, since the optical scanner of the present embodiment has somewhat similar construction to that of the optical scanner of the preceding embodiment, substantially like components are denoted by like reference numerals and overlapping description thereof is omitted herein to avoid redundancy.
  • The optical scanner of the present embodiment includes a mirror 36 for changing the advancing direction of diffused signal light condensed by a condenser lens 28 and adopts a hollow rotary polygon mirror 32 comprising a substantially hexagonal tube which is open at the top thereof. A plurality (six in the present embodiment) of reflecting portions 34 are provided on an inner periphery of the rotary polygon mirror 32 and are each constituted from a pair of opposing reflecting faces 34a and 34b. The reflecting faces 34a and 34b of the reflecting portions 34 are disposed such that such a scanning pattern which is composed of a plurality of scanning lines of various directions as seen in FIG. 7 may be obtained similarly as in the embodiment described above.
  • Since the optical scanner of the present embodiment has such construction as described just above, a scanning pattern constituted from a plurality of scanning lines of various directions can be obtained using only the rotary polygon mirror 32 similarly as in the optical scanner of the preceding enbodiment.
  • Accordingly, such a hologram disk or a set of reflecting mirrors as is required in a conventional optical scanner is eliminated, which enables miniaturization and reduction in cost of the arrangement. The optical scanner of the present embodiment further has such advantages as those of the optical scanner of the embodiment described hereinabove.
  • It is to be noted that, while the optical scanners of both the embodiments described above are constituted such that each of the reflecting portions of the rotary polygon mirror has a pair of reflecting faces having different inclination angles with respect to the axis of rotation of the rotary polygon mirror, the number of such reflecting faces of each reflection portion is not limited to two. For example, as shown in FIG. 9, each reflecting portion 38 may include three reflecting faces 38a, 38b and 38c having different inclination angles with respect to the axis of rotation of the rotary polygon mirror.

Claims (10)

1. A rotary reflecting device (18; 32) for use in optical scanning apparatus, which device (18; 32) is rotatable about an axis of rotation therethrough and has a plurality of reflectors (20; 38) positioned at respective different angular locations around that axis, characterised in that each of the said reflectors (20; 38) has two mutually-adjacent substantially planar reflecting faces (20a, 20b; 38a, 38b) which meet in a line (21) of intersection that is inclined with respect to the said axis of rotation, and in that the respective said lines (21) of intersection of adjacent reflectors (20; 38) of the device are inclined respectively at different angles (ϑ₁) with respect to the said axis of rotation.
2. A device as claimed in claim 1, wherein the angle (ϑ₂) between the said two reflecting faces (20a, 20b; 38a, 38b) of each reflector is different from the angle (ϑ₂) between the said two reflecting faces of an adjacent reflector of the device.
3. A device as claimed in claim 1 or 2, wherein each of the said reflectors (38) has a third substantially planar reflecting face (38c) which meets one of the other faces (38a, 38b) at a further line of intersection.
4. An optical scanner for scanning coded bars by means of a laser beam to read a bar code of the coded bars, comprising:
a light source for generating a laser beam;
a rotary polygon mirror having a plurality of reflecting portions provided thereon around an axis of rotation thereof for reflecting the laser beam from said light source toward the coded bars, each of said reflecting portions of said rotary polygon mirror including a plurality of flattened reflecting faces having different inclination angles from each other with respect to the axis of rotation such that an inclination angle of a line of intersection between adjacent ones of said flattened reflecting faces of each of said reflecting portions with respect to the axis of rotation is different from an inclination angle of a line of intersection between adjacent ones of said flattened reflecting faces of each of adjacent ones of said reflecting portions on the opposite sides of the reflecting portion with respect to the axis of rotation; and
a photodetector for detecting diffused signal light diffused by the coded bars.
5. An optical scanner according to claim 4, wherein an included angle between adjacent ones of said flattened reflecting faces of each of said reflecting portions of said rotary polygon mirror is different from an included angle between adjacent ones of said flattened reflecting faces of adjacent ones of said reflecting portions on the opposite sides of the reflecting portion.
6. An optical scanner according to claim 4 or 5, wherein said rotary polygon mirror has six reflecting portions, and each one of each pair of said reflecting portions which are positioned on the opposite sides with respect to the axis of rotation has a plurality of flattened reflecting faces which have the same arrangement as those of the other one of said pair of reflecting portions.
7. An optical scanner according to claim 4, 5 or 6, wherein said reflecting portions are provided on an outer periphery of said rotary polygon mirror.
8. An optical scanner according to claim 4, 5 or 6, wherein said rotary polygon mirror has a tubular configuration which is open at the top thereof, and said reflecting faces are provided on an inner periphery of said tubular rotary polygon mirror.
9. A rotary polygon mirror adapted to produce a scanning pattern constituted from a plurality of scanning lines of different directions, said rotary polygon mirror having a plurality of reflecting portions provided around an axis of rotation thereof, each of said reflecting portions having a plurality of flattened reflecting faces having different inclination angles from each other with respect to the axis of rotation such that an inclination angle of a line of intersection between adjacent ones of said flattened reflecting faces of each of said reflecting portions with respect to the axis of rotation is different from an inclination angle of a line of intersection between adjacent ones of said flattened reflecting faces of each of adjacent ones of said reflecting portions on the opposite sides of the reflecting portion with respect to the axis of rotation.
10. A rotary polygon mirror according to claim 9, wherein an included angle between adjacent ones of said flattened reflecting faces of each of said reflecting portions of said rotary polygon mirror is different from an included angle between adjacent ones of said flattened reflecting faces of adjacent ones of said reflecting portions on the opposite sides of the reflecting portion.
EP90304305A 1989-04-20 1990-04-20 Rotary reflecting devices for use in optical scanning apparatus Expired - Lifetime EP0394072B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP101000/89 1989-04-20
JP1101000A JP2771593B2 (en) 1989-04-20 1989-04-20 Optical scanning device

Publications (3)

Publication Number Publication Date
EP0394072A2 true EP0394072A2 (en) 1990-10-24
EP0394072A3 EP0394072A3 (en) 1991-11-13
EP0394072B1 EP0394072B1 (en) 1995-07-05

Family

ID=14289009

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90304305A Expired - Lifetime EP0394072B1 (en) 1989-04-20 1990-04-20 Rotary reflecting devices for use in optical scanning apparatus

Country Status (4)

Country Link
US (1) US5000529A (en)
EP (1) EP0394072B1 (en)
JP (1) JP2771593B2 (en)
DE (1) DE69020626T2 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0424096B1 (en) * 1989-10-16 1996-09-18 Fujitsu Limited Bar code readers
EP0926582A1 (en) * 1997-12-24 1999-06-30 Datalogic S.P.A. Apparatus and process for focusing a laser beam for optical codes
EP2693256A1 (en) * 2012-08-01 2014-02-05 Delphi Technologies, Inc. Windshield display with obstruction detection
CN113678048A (en) * 2019-02-07 2021-11-19 川崎重工业株式会社 Polygonal mirror, light guide device, and optical scanning device

Families Citing this family (56)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0833905B2 (en) * 1989-05-24 1996-03-29 日本電気株式会社 Bar code reader
US5268565A (en) * 1989-10-16 1993-12-07 Fujitsu Limited Compact type bar code reader
FR2656430B1 (en) * 1989-12-26 1994-01-21 Telecommunications Sa SCANNING DEVICE AND ITS APPLICATION TO ANALYSIS DEVICES.
US5206491A (en) * 1990-03-02 1993-04-27 Fujitsu Limited Plural beam, plural window multi-direction bar code reading device
US5286961A (en) * 1990-05-23 1994-02-15 Tokyo Electric Co., Ltd. Bar code reader producing two groups of vertical scan lines and two groups of inclined scan lines on a plane normal to the read window
US5942743A (en) * 1994-08-17 1999-08-24 Metrologic Instruments, Inc. Portable automatic hand-supportable omnidirectional laser projection scanner with power conserving control system
US6182898B1 (en) 1993-11-24 2001-02-06 Metrologic Instruments, Inc. Bar code scanner with intuitive head aiming and collimated scan volume
US6098885A (en) * 1990-09-10 2000-08-08 Metrologic Instruments Countertop projection laser scanning system for omnidirectional scanning volume projected above a countertop surface of code symbols within a narrowly-confined scanning
US5796091A (en) * 1993-11-24 1998-08-18 Metrologic Instruments, Inc. Automatic hand-supportable omnidirectional laser projection scanner with handle-controllable projection axis
US6286760B1 (en) 1994-08-17 2001-09-11 Metrologic Instruments, Inc. Automatic hand-supportable laser projection scanner for omni-directional reading of bar code symbols within a narrowly confined scanning volume
US6651890B2 (en) 1990-09-10 2003-11-25 Sung Ho Byun Combination hand-held and counter-top omnidirectional scanner
US5216232A (en) * 1990-09-10 1993-06-01 Metrologic Instruments, Inc. Projection laser scanner producing a narrow scan volume
US6257492B1 (en) 1990-09-10 2001-07-10 Peter Bressler Combination hand-held and counter-top omni-directional scanner
US5844227A (en) * 1993-11-24 1998-12-01 Metrologic Instruments, Inc. Automatic hand-supportable omnidirectional laser projection scanner with scan-head directed projection axis for intuitive hand-supported omnidirectional scanning of bar code symbols within a narrowly confined scanning volume extending thereabout
US5192857A (en) * 1990-09-28 1993-03-09 Ncr Corporation Compact optical scanner rotatable between horizontal and vertical positions
US5081364A (en) * 1990-11-26 1992-01-14 Ncr Corporation Multifocal scanning system
US5115122A (en) * 1990-12-12 1992-05-19 Ncr Corporation Compact optical scanning system
JP3354162B2 (en) * 1991-04-26 2002-12-09 富士通株式会社 Scanning device
US5179271A (en) * 1991-09-19 1993-01-12 Ncr Corporation Compact optical scan pattern generator for bar code reading systems
US5229588A (en) * 1991-09-30 1993-07-20 Ncr Corporation Dual aperture optical scanner
US5202784A (en) * 1992-01-10 1993-04-13 Spectra-Physics Scanning Systems, Inc. Optical system for data reading applications
US6860427B1 (en) 1993-11-24 2005-03-01 Metrologic Instruments, Inc. Automatic optical projection scanner for omni-directional reading of bar code symbols within a confined scanning volume
US6604684B1 (en) 1993-11-24 2003-08-12 Metrologic Instruments Inc. Automatic optical projection scanner for omni-directional reading of bar code symbols within a confined scanning volume
US6758402B1 (en) 1994-08-17 2004-07-06 Metrologic Instruments, Inc. Bioptical holographic laser scanning system
US7051922B2 (en) * 1994-08-17 2006-05-30 Metrologic Instruments, Inc. Compact bioptical laser scanning system
US6032861A (en) * 1995-01-03 2000-03-07 Lemelson; Jerome H. Method and apparatus for encoding and decoding bar codes with primary and secondary information and method of using such bar codes
US6543691B1 (en) * 1995-01-03 2003-04-08 Jerome H. Lemelson Method and apparatus for encoding and decoding bar codes with primary and secondary information and method of using such bar codes
JP3441580B2 (en) 1995-12-14 2003-09-02 富士通株式会社 Reader
US6575368B1 (en) 1996-01-31 2003-06-10 Psc Scanning, Inc. Multiple aperture data reader for multi-mode operation
US5962838A (en) * 1996-07-15 1999-10-05 Psc Scanning, Inc. Barcode scanner with manually switchable scan patterns
US5979761A (en) * 1996-11-18 1999-11-09 Accu-Sort Systems, Inc. Bar code laser scanner having a plurality of adjustable mirrors
IT1289438B1 (en) * 1996-12-11 1998-10-15 Datalogic Spa SCANNING READER OF AN OPTICAL CODE PLACED ON A MOVING ARTICLE AND METHOD OF SCANNING OF SAID OPTICAL CODE BY MEANS OF SAID
ATE289691T1 (en) * 1997-07-18 2005-03-15 Datalogic Spa DEVICE AND METHOD FOR READING AN OPTICAL CODE
JP3881792B2 (en) 1998-10-21 2007-02-14 富士通株式会社 Optical scanning device, code reading device, and bar code reading device
US6543694B1 (en) * 1999-03-29 2003-04-08 Ncr Corporation Extended coverage barcode scanner
US6918540B2 (en) * 2000-04-18 2005-07-19 Metrologic Instruments, Inc. Bioptical point-of-sale (pos) scanning system employing dual polygon-based laser scanning platforms disposed beneath horizontal and vertical scanning windows for 360° omni-directional bar code scanning
US20030132291A1 (en) * 2002-01-11 2003-07-17 Metrologic Instruments, Inc. Point of sale (POS) station having bar code reading system with integrated internet-enabled customer-kiosk terminal
US7100832B2 (en) * 2000-04-18 2006-09-05 Metrologic Instruments, Inc. Bioptical laser scanning system providing 360° of omnidirectional bar code symbol scanning coverage at point of sale station
JP4330762B2 (en) 2000-04-21 2009-09-16 富士フイルム株式会社 Multi-beam exposure system
US7083102B2 (en) * 2002-01-11 2006-08-01 Metrologic Instruments, Inc. Bioptical laser scanner for six-sided 360° Pos-based scanning
US6874690B2 (en) * 2002-01-11 2005-04-05 Metrologic Instruments, Inc. Modular omnidirectional bar code symbol scanning system with at least one service port for removable installation of scan module insert
US7296748B2 (en) * 2002-01-11 2007-11-20 Metrologic Instruments, Inc. Bioptical laser scanning system providing 360° of omnidirectional bar code symbol scanning coverage at point of sale station
US20060217695A1 (en) * 2003-12-31 2006-09-28 Debenedictis Leonard C Optically-induced treatment of internal tissue
US7372606B2 (en) * 2003-12-31 2008-05-13 Reliant Technologies, Inc. Optical pattern generator using a single rotating component
AU2011211420B2 (en) * 2005-02-14 2012-05-24 Solta Medical, Inc. Optical pattern generator using a single rotating component
US7992785B2 (en) * 2006-06-26 2011-08-09 Ncr Corporation Mirrored spinner with paired offset facets
WO2008144769A1 (en) * 2007-05-21 2008-11-27 Reliant Technologies, Inc. Optical pattern generator using a single rotating optical component with ray-symmetry-induced image stability
DE102009054888A1 (en) * 2009-12-17 2011-06-22 Carl Zeiss SMT GmbH, 73447 Optical element with a plurality of reflective facet elements
US8678285B2 (en) * 2011-09-20 2014-03-25 Metrologic Instruments, Inc. Method of and apparatus for multiplying raster scanning lines by modulating a multi-cavity laser diode
US8523076B2 (en) 2012-01-10 2013-09-03 Metrologic Instruments, Inc. Omnidirectional laser scanning bar code symbol reader generating a laser scanning pattern with a highly non-uniform scan density with respect to line orientation
US10078132B2 (en) * 2013-04-11 2018-09-18 Konica Minolta, Inc. Scanning optical system and radar
US10048492B2 (en) * 2014-10-07 2018-08-14 Konica Minolta, Inc. Scanning optical system and radar
WO2016056543A1 (en) * 2014-10-07 2016-04-14 コニカミノルタ株式会社 Scanning optical system and radar
JP6618042B2 (en) * 2014-10-09 2019-12-11 コニカミノルタ株式会社 Emitter / receiver
EP3330766B1 (en) * 2015-07-27 2019-02-27 Konica Minolta, Inc. Mirror unit and optical-scanning-type object detection device
CA3113404C (en) 2018-10-02 2022-06-14 Blackmore Sensors & Analytics, Llc Method and system for optimizing scanning of coherent lidar

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2503391A1 (en) * 1981-03-31 1982-10-08 Ferranti Plc OPTICAL SCANNING SYSTEM
EP0278332A1 (en) * 1987-01-30 1988-08-17 Canon Kabushiki Kaisha Beam deflector and laser beam printer using same
EP0283717A2 (en) * 1987-03-20 1988-09-28 Josef-Ferdinand Dipl.-Ing. Menke Opto-mechanical device

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1569879A (en) * 1975-12-13 1980-06-25 Barr & Stroud Ltd Radiation scanning system
US4413878A (en) * 1977-09-13 1983-11-08 The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland Imaging systems
US4753498A (en) * 1985-03-22 1988-06-28 Tokyo Kogaku Kikai Kabushiki Kaisha Optical reader
US4799164A (en) * 1986-09-12 1989-01-17 Spectra-Physics, Inc. Shallow bar code scanner
JPS63292108A (en) * 1987-05-25 1988-11-29 Canon Inc Optical scanning device
JP2642646B2 (en) * 1987-12-01 1997-08-20 株式会社テック Optical scanning reader
JPH02197811A (en) * 1989-01-27 1990-08-06 Fujitsu Ltd Device for forming scanning pattern

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2503391A1 (en) * 1981-03-31 1982-10-08 Ferranti Plc OPTICAL SCANNING SYSTEM
EP0278332A1 (en) * 1987-01-30 1988-08-17 Canon Kabushiki Kaisha Beam deflector and laser beam printer using same
EP0283717A2 (en) * 1987-03-20 1988-09-28 Josef-Ferdinand Dipl.-Ing. Menke Opto-mechanical device

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0424096B1 (en) * 1989-10-16 1996-09-18 Fujitsu Limited Bar code readers
EP0926582A1 (en) * 1997-12-24 1999-06-30 Datalogic S.P.A. Apparatus and process for focusing a laser beam for optical codes
US6325289B1 (en) 1997-12-24 2001-12-04 Datalogic S.P.A. Apparatus and process for focusing a laser beam for reading optical codes
EP2693256A1 (en) * 2012-08-01 2014-02-05 Delphi Technologies, Inc. Windshield display with obstruction detection
CN113678048A (en) * 2019-02-07 2021-11-19 川崎重工业株式会社 Polygonal mirror, light guide device, and optical scanning device
EP3923057A4 (en) * 2019-02-07 2022-10-26 Kawasaki Jukogyo Kabushiki Kaisha Polygon mirror, light guide device, and optical scanning device
CN113678048B (en) * 2019-02-07 2023-10-27 川崎重工业株式会社 Polygonal mirror, light guide device, and optical scanning device

Also Published As

Publication number Publication date
US5000529A (en) 1991-03-19
EP0394072A3 (en) 1991-11-13
DE69020626T2 (en) 1995-11-30
JP2771593B2 (en) 1998-07-02
DE69020626D1 (en) 1995-08-10
EP0394072B1 (en) 1995-07-05
JPH02278222A (en) 1990-11-14

Similar Documents

Publication Publication Date Title
EP0394072B1 (en) Rotary reflecting devices for use in optical scanning apparatus
KR940002961B1 (en) Multi-directional barcode reading device
EP0348232B1 (en) Optical beam scanner for reading bar-codes
EP0402952B1 (en) Scan pattern generators for bar code symbol readers
US4871904A (en) Multidirectional optical scanner
US5466921A (en) Scanner to combine partial fragments of a complete code
US5268565A (en) Compact type bar code reader
US5221832A (en) Raster variation method for omnidirectional optical scanners
US6045046A (en) Full coverage barcode scanner
EP0396485B1 (en) Bar code scanner with a large depth of field
US5464972A (en) Omnidirectional bar code label scanner
EP0572685B1 (en) A symbol reading device for varying the focal point of a scanning laser beam through variance of scanning laser beam optical path length
US5223700A (en) Bar code reader having a polygon mirror providing different scan line lengths
US5975418A (en) Bar code scanner with increased number of scanning beams having different directions
US5173603A (en) Focus changing apparatus and method for optical scanners
EP0373934A3 (en) Hand-held bar code reader
US5610385A (en) Optical bar code scanner which produces substantially perpendicular scan lines
EP0424096B1 (en) Bar code readers
CA2020540C (en) Bar code reader
EP0485029A1 (en) Optical bar code reader device
JP2729171B2 (en) Rotary scanning line barcode scanner
JPH07168905A (en) Bar code scanner
JPH0312286B2 (en)
JPS63298214A (en) Beam switching device
JP2760161B2 (en) Reader

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR GB

17P Request for examination filed

Effective date: 19920403

17Q First examination report despatched

Effective date: 19931110

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REF Corresponds to:

Ref document number: 69020626

Country of ref document: DE

Date of ref document: 19950810

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20060410

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20060413

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20060419

Year of fee payment: 17

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20070420

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20071101

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070420

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070430